org.apache.commons.io.comparator

Class CompositeFileComparator

java.lang.Object

org.apache.commons.io.comparator.AbstractFileComparator

org.apache.commons.io.comparator.CompositeFileComparator

All Implemented Interfaces:

java.io.Serializable, java.util.Comparator<java.io.File>

public class CompositeFileComparator
extends AbstractFileComparator
implements java.io.Serializable

Compare two files using a set of delegate file Comparator.

This comparator can be used to sort lists or arrays of files by combining a number of other comparators.

Example of sorting a list of files by type (i.e. directory or file) and then by name:

       CompositeFileComparator comparator = new CompositeFileComparator(
           DirectoryFileComparator.DIRECTORY_COMPARATOR,
           NameFileComparator.NAME_COMPARATOR);
       List<File> list = ...
       comparator.sort(list);
 

Deprecating Serialization

Serialization is deprecated and will be removed in 3.0.

Since:

2.0

See Also:

Serialized Form

Field Summary

Fields

Modifier and Type	Field and Description
private java.util.Comparator<java.io.File>[]	delegates Delegates.
private static java.util.Comparator<?>[]	EMPTY_COMPARATOR_ARRAY
private static long	serialVersionUID

Constructor Summary

Constructors

Constructor and Description
CompositeFileComparator(java.util.Comparator<java.io.File>... delegates) Constructs a composite comparator for the set of delegate comparators.
CompositeFileComparator(java.lang.Iterable<java.util.Comparator<java.io.File>> delegates) Constructs a composite comparator for the set of delegate comparators.

Method Summary

Modifier and Type	Method and Description
int	compare(java.io.File file1, java.io.File file2) Compares the two files using delegate comparators.
private java.util.Comparator<java.io.File>[]	emptyArray()
java.lang.String	toString() String representation of this file comparator.

Methods inherited from class org.apache.commons.io.comparator.AbstractFileComparator

sort, sort

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Methods inherited from interface java.util.Comparator

comparing, comparing, comparingDouble, comparingInt, comparingLong, equals, naturalOrder, nullsFirst, nullsLast, reversed, reverseOrder, thenComparing, thenComparing, thenComparing, thenComparingDouble, thenComparingInt, thenComparingLong

Field Detail

EMPTY_COMPARATOR_ARRAY

private static final java.util.Comparator<?>[] EMPTY_COMPARATOR_ARRAY

serialVersionUID

private static final long serialVersionUID

See Also:

Constant Field Values

delegates

private final java.util.Comparator<java.io.File>[] delegates

Delegates.

Constructor Detail

CompositeFileComparator

public CompositeFileComparator(java.util.Comparator<java.io.File>... delegates)

Constructs a composite comparator for the set of delegate comparators.

Parameters:

delegates - The delegate file comparators

CompositeFileComparator

public CompositeFileComparator(java.lang.Iterable<java.util.Comparator<java.io.File>> delegates)

Constructs a composite comparator for the set of delegate comparators.

Parameters:

delegates - The delegate file comparators

Method Detail

compare

public int compare(java.io.File file1,
                   java.io.File file2)

Compares the two files using delegate comparators.

Specified by:

compare in interface java.util.Comparator<java.io.File>

Parameters:

file1 - The first file to compare

file2 - The second file to compare

Returns:

the first non-zero result returned from the delegate comparators or zero.

emptyArray

private java.util.Comparator<java.io.File>[] emptyArray()

toString

public java.lang.String toString()

String representation of this file comparator.

Overrides:

toString in class AbstractFileComparator

Returns:

String representation of this file comparator